Rock-drilling mechanism



March 17, 1931. T, R E, RUNDQWST 1,796,667

' ROCK DRILLING MEGHANISM Original Filed Oct. 12, 1925 Patented Mar. 17, 1931 UNITED sizarlr-:s1N

PATENT OFFICE THOBE R. `E. RUNDQVIST, OF CLAREMONT, NEW` HAMPSHIRE, ASSIGNOR TO SULLIVAN i MACHINEIR-Y` COMPANY, A CORPORATION OF MASSACHUSETTS ROCK-DRILLING MECHANISM Application filed October 12, 1923, Serial No. 668,197. Renewed October 10, 1929.

My invention relates to rock mechanisms.

An object of mv invention is to provide drilling `an improved rock drilling mechanism. An-

- erated pereussive type. A further objectoij my invention is to provide an improved controlling mechanism for the pneumatic feeding mechanism of'a rock drill of the pressure fluid operated percussive type, and more particularly one adapted to control the pressure in the feeding means during spotting of the hole. A still further object of my invention is to provide an improved controlling mechanism which is automatically controlled by the variations in pressure Within the feeding means and more particularly adapted to prevent accidental collapse of the feed. These and other objects and advantages of my invention will hereinafter more fully appear.

In the accompanying drawings I have shown for purposes of illustration one form that my invention may assume inpractice.

In these draWings,--

lii'g. l is a iront elevation, partially broken awry` of a drilling mechanism in which my improved feed controllingV mechanism is incorporated.

Eig. 2 is a central longitudinal sectional view'talen substantially on line Q-Q of Fig. 1.

Fig. 3 is a transverse sectional view taken substantially on line 3-3 of Fig. 2.

Fig. l is a detail view of a part of my improved controlling mechanism.

Fig. is a detail sectional view, taken substantially on line 5 5 of Fig. 1, through the throttle valve, showing the motor and feed supply ports. i

In this illustrative form of my invention I have shown a drilling mechanism of the .so-called stoper type generally designated 1, which comprises a drilling motor 2 of the pressure fluid percussive type Which is` adapted to percussively aetuate a drill steel 3 carried in the front end of the drilling mechanism.` and a feeding mechanism generally designated 4l of the pressure fluid operated type. `This feeding mechanism comprises a feed cylinder 5 and a. piston 6 reciprocable therein having a piston rod 7 provided with a point 8 adapted to engage an extraneous abutment during the drilling operation. The drilling motor parts and the feeding mechanism are suitably held together by means of side rods including bolt heads or nuts 9, in a Well known manner. Suitably secured in a head member 10 of the drilling motor is a laterally projecting handle 11 having a. grasping portion 12 which is used for supporting the drilling mechanism during the drilling operation and to rotate the drill steel 3 if automatic rotation is not present.

suitably secured in a boss 13 formed integral With the head block l() is a valve bushing 14, which has a conical bore 15 formed therein in which a throttle valve 16 is disposed. Herein, the throttle valve has a hollovved out portion 17 to which pressure liuid is admitted through a swiveled pipe connection 18 from any suitable` source of supply. The throttle valve 16 is traversed by a port 19 which is adapted to be connected to a passage 20 (see Fig. Q) leading to the distribution ports of the drill.- ing motor in a wellknoivn manner. A bore 21 is formed coaxially in the valve 16 and communicates at its forward end b v a port 22 with the chamber 17. Opening laterally from the bore 21 is a port 2?) communicating with a groove Qf-l elctending longitudinally of the valve in the periphery thereof. Herein the groove `2l connnunicates With a circumferentially extending `groove 25 which in turn communicates With a port 26 leading to the interior of the feed cylinder. An auxiliary control valve 27 having a generally conical end 28 is longitudinally reciprocable in the bore 2l and is provided with a head or collar 29 against which a spring 30 presses to maintain the valve in Wide open position, thereby permitting communication between the ports 22 and 23. A small passage 31 extends longitudinally of the valve 27 which is adapted to communicate by way of a port 32 with the port 23 lleading to the feed cylinder and to the atventing the feed Cylinder to the atmosphere Y through the passage 31.

Gircumferentially spaced from the port 19 in the throttle valve 16 is a port 36 which isadapted to y communicate with a port 37 leading to my improved automatic feedv controlling'mechanism to be now described.

Herein it will be noted that the piston rod 7 is provided with a hollow bore 38 throughout its length in-which a sleeve member 39 is'reciprocable. The sleeve 39 is provided with a plurality of oppositely disposed slots or grooves 40 and 41, in which grooves 46 a plurality of friction springs 42 Vare disposed. These springs are adapted to frictionally engage the walls of the boref38 tending to hold the` sleeve stationary. Longitudinally reciprocable in a bore 43 formed inthe sleeve 39 is a cylindrical slide valve 44 which is suitably secured to an inner head member 10', suitably secured to the head block 10 by means of a hollow rod 45, which is in turn threaded as at 46 and 47, respectively, to the valve and the head member 10.` The valve is provided with alongitudinally extending bore 43 and is perforated by a series of ports 49 which are adapted4 tok communicate with av series ports 50 formed in the sleeve 39. Pressure fluid isadapted to be adinitted to the bore 48 by means of the passage 37 leading from the valve 16. The opposite ends of the valve 44 are provided with stop members 51" and 52 with which the sleeve 39 is adapted to engage under certain conditions.

ln the operation of my improved mechanism, the point 3`of the vfeed piston rod 7 is placed against an abutment a suitable distance from the working face, theV drilling mechanism being supported by the handle 1l at this time. The operator then manipulates the valve 16 to the position -shownin Fig. 2 and Fig. 5, .bringing the grooves 24 and 25 which communicate vit-h the pressure fluid supply chamber 17 into communication with the ports 26 and '37 admitting fluid pressure tothe feed cylinder from the chamber 17 through ports 22 and 23, grooves 24 and 25 and port 26y under control of the valve 27 and causing the feed cylinder to move upwardly relative to the feed piston, consequently bringing the drill steel adjacent the-work, the ports 49 and v56 being closed at this time as shown in Fig. 2. The'feed control valve 27 lis then closed by swinging the lever 33 to the left in Fig. 1, thereby cutting off the air supply to the feed cylinder through the port 26 and opening the port 31 venting the feed cylinder to atmosphere, consequently stopping the feed. As a result of this reductionV of pressure in the feed cylinder the drilling motor, the feed cylinder, the rod 45, and the valve 44 will fall downwardly relative to the feed ypiston rod, the stop 51 engaging the sleeve 39 4and thereby opening the communication between the ports 49 and 50. This will cause a greater amount of pressure air to flow from the hollow rod into the feed cylinder than is being vented out throughcthe vent 31, so the drill will again move up tothe work. Communication between the ports 49 and again is eut off by the sleeve 39 which frictionally engages the bore of the stationary piston rod. The pressure again drops in the feed cylinder, the vent passage 31 still remaining'open, again causing the drilling motor and feed cylinder to drop back relative to the feed piston, again opening communication between'the ports 49 and 50, simultaneously again moving the ports 49 .out of communication with the ports 50,

the sleeve 39 tending` to remain stationary, by means of the springs 42 engaging the walls of the bore 38, until the stop 52 engages the valve, the sleeve and valve thereafter moving simultaneously until the drill againfalls baclr. This operation is repeated as long as the vent passage 31 remains open substantially balancing the feed within the limits of the stop members 51 and 52 with the drill steel 3 positioned at the desired distance from the working face. he valve 16 is then further rotated bringing the port 19 in communication with the passage 20, thereby starting the drilling motor and spotting the hole. After the hole is spotted the lever 33 is released causing the passage 31 to be closed,V the drill again moving forwardly by means of pressure fluid passing through the port 26. The ports 49 and 50 are closed during the forward feed of the drilling` motor as shown in Fig. 2. lt will also be noted if a soft spot or seam is encountered during the drilling operation, the jumping of the drill is prevented by quickly closing the valve 27 consequently cut-ting off the flow of fluid through passage 26. vt is also obvious that the falling of the vdrilling mechanism in this case is also prevented by the automatic control valve 44. lt will herein also be 'notedthat when the supply of fluid to the feed cylinder 5 and. the vent port 31 is closed with only the supply of fluid to the conduit 45 open the pressure fluid is trapped in the feed cylinder and as this pressure graduallv reduces, due to inherent leakagen between the feeding parts, the feed cylinder moves rea wardly relative to the stationary feed pis- Cil ton. Such rearward movement causes the ports 49 in the slide valve 44 to move into. communication with the part-s 5() in the sleeve 39, thus admitting a supplemental supply of pressure fluid from the conduit` 4:5 to the feed cylinder, thereby automatically maintaining the pressure therein above a predetermined minimum and preventing the dropping of the drill steel away from the work. A

As a result of my improvement it will be obvious that the feed during spotting may be readily controlled and that the accidental falling of the drill caused by the drop in pressure above the piston in the feed cylinder is entirely eliminated, thereby preventing the flying of the drill steel and thefalling of the drilling mechanism wl'lich frequently injures the operator and damages the drill. It will also be noted that falling of the drill, caused by the operator unwittingly closing off the feed while maintaining the motor ruiming, is prevented. It will also further be noted that the controln ling mechanism is of simple structure and that it may be applied to a drill of standard form with a minimum of change.

lVhile I have in this application specifi cally described one form which my invention may assume in practice, it will be understood that this form of the same is shown for purposes of illustration and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

l. In a rock drilling mechanism, the combination with a drilling motor, and fluid actuated feeding means therefor comprising cooperating feeding members adapted to have relative movement, of feed controlling means for controlling said relative movement comprising a controlling element movable with one of said feeding members and a cooperating controlling element engageable with the other feeding member, said controlling elements being movable rel ative to each other upon relative movement of said feeding members in one direction for controlling fluid flow to said feeding means.

`2. In a rock drilling mechanism, the combination with a drilling motor, and fluid actuated feeding means therefor comprising cooperating feeding members adapted to have relative movement, of fluid controlling means for said feeding means for effecting relative movement between said members comprising cooperating relatively Vmovable controlling element-,s engageable respectively with said feeding members, one of said controlling elements slidably engaging one of said feeding members.

'3. In a rock drill, the combination with a drilling motor, and fluid actuated feeding mechanism therefor comprising a stationary member and a movable member, of means for controlling the flow of fluid to said feeding mechanism including an element carried by said movable feeding member and a cooperating element slidably engageable with said stationary feeding member.

4. In a rock drill, the combination with a drilling motor, fluid actuated feeding mechanism therefor comprising a source of pressure fluid, cooperating feed cylinder and piston members adapted to have relative movement, and means for controlling the connection of said source with said cylinder, of supplemental fluid controlling means for said feeding mechanism including a controlling element carried by one of said feeding members, and a cooperating controlling element engageable with the other feeding member, said controlling elements being relatively movable upon relative movement of said feeding members in one direction for controlling fluid flow to said feeding means.

5. In a rock drill, the combination with` a drilling motor, and fluid actuated feeding mechanism therefor comprising cooperating feed cylinder and piston members adapted to have relative movement, of means for controlling the pressure in said feed cylinder including a valve element carried with the latter and a cooperating valve element engageable with said piston, one of said valve elements being movable relative to the other to control fluid flow to s aid feeding mechanism.

6. In a rock drill, the combination with a drilling motor, and fluid actuated feeding mechanism therefor comprising a plurality of cooperatingv feeding members adapted to have relative movement, of means for controlling the llow of fluid to said feeding mechanism including a valve element cai ried with one of said feeding members and a cooperating valve element frictionally engageable with the other feeding member.

7. In a rock drill, the combination with a drilling motor, and fluid actuated feeding mechanism therefor comprising cooperatingI relatively movable cylinder and piston meinbers, of means for controlling the pressure to said feed cylinder including a controlling element carried with one of` said feeding members, and a cooperating controlling element frictionally engageable with the other feeding member,

8. In a drilling mechanism, the combinzn tion with a drilling motor, feeding means therefor including relatively movable feed-` ing elements, means forsupplying pressure fluid to said feeding means for actuating the latter including separate passages, man ual means for controlling one of said .pas`- sages, of means operative upon relative movement between said feeding elements lil) for automatically controlling another pas-V sage Awhen's'aid first vpassage Yis closed by said manual means, said automatic means being operative when the pressure in said feeding means drops below a predetermined minimum and including controlling elements respectively engaging said feeding elements.

9J In a drilling mechanism, the combination with a drilling motor, and feeding means therefor including a cylinder and cooperating piston, of means for automatically controlling the pressure fluid supply to said feeding means including cooperating elements one movable with said drilling motor and another frictionally engageable with one of said feeding elements.

10. In a drilling mechanism, the combination with a drilling motor, pressure fluid actuated feeding' means therefor including relatively movable elements, and a source of pressure fluid, of mechanically actuated means dependent upon movement between said feedingV elements in one direction for openingautomatically communication between said source and said feeding means thereby maintaining the pressure inthe latter above a' predetermined minimum, said means vbeing automatically operative to supply fluid to said feeding means when the pressure therein drops below said :minimum pressure.

11. In a drilling mechanism, the combination with a drilling motor, pressure fluid actuated feeding'means therefor including relatively movable feeding elements, and means for normally controlling the supply of fluid thereto, of mechanically actuated means dependent upon relative movement between said feeding elements to maintain automatically a predetermined pressure in said feeding means when said first mentioned `fluid supply is closed by vsaid controlling means.

l2. In a drillingmechanism, the combination with a drilling motor, pressure fluid actuated feeding means therefor incliu'ling a. stationary member and a movable member, and a source of pressure fluid, of means including cooperating fluid controlling elements-engageable respectively with said members and dependent upon relative movement between said feeding members to open automatically communication between said source and said feeding means when the pressure in said feeding means drops below a predetermined minimum.

13. In a drilling mechanism, the combinationy with a drilling motor, a drill steel Y actuated thereby, pressure fluid actuated feedingV means therefor. including relatively movable feeding elements, and means normally controlling the'llow of fluid thereto, of mechanically actuated, supplemental fluid controllingfmeans dependent upon relative movement between saidfccding elements to maintain automatically the drill steel in substantially operative position adjacent the Work when the normal flow of fluid to said feeding means is closed by said controlling means.

14. In a drilling mechanism, the combination with a drilling motor, a drill steel actuated thereby, pressure iluidfactuated feedl. ing means therefor including a stationary member and amovable member, and means for normally controlling the flow of fluid thereto, of means includingY cooperating fluid controlling elements engageable respectively with saidfeeding members and automatically operative to maintain the drill steel in substantially operative vposition adjacent the work when the normal flow of fluid to said feeding means is closed by said first mentioned controlling means. Y

l5.V In a drilling mechanism, the combination with a drilling motor, pressure fluid actuated feeding means therefor including a stationary member and a movable member, and controllingmeans for opening and closing a supply of fluid to said feeding means, of means including cooperating fluid controlling elements engageable respectively With said members and automatically operative upon relative movement between said feeding members to maintain a predetermined pressure in said feeding means when said fluid controlling means is closed. 16. In a drilling mechanism, the combination with a drilling motor, a drill steel actuated thereby, pressure fluid actuated feeding means fory said steel ,including a movable feed cylinder and a cooperating stationary feed piston, means for normally supplying-pressureV fluid to said feeding means, and controlling means for opening and closing said normal fluid supply, of means including cooperating fluid controlling elements engageable respectively with said cylinder and piston and operative upon relative movement between said cylinder andpistou for automatically maintaining the pressure in said feeding meansup to a degree sufficient to maintain the drill steel adjacent the work when said normal fluid supply is closed by said first mentioned controlling means. j f

17. In a drilling mechanism, the combination with a drilling motor, a drill steel actuated thereby, pressure Y fluid' actuated feeding means therefor including relatively movable Vvfeeding-elements, and manually operable means for normally controlling the flow of fluid thereto, of mechanically actuated means positively actuated upon relative movement between said feeding elements and automatically operative to substantially balance by pressure fluid the drill steel iii position adjacent the work when the normal fluid supply to said feeding means is closed iii manually operable controlling away from "the `ivorl.

19. In a drilling mechanism, the combination with a drilling motor, a drill steel actuated thereby, and pressure fluid actu ated feeding means therefor including a stationary member and a movable member, of means Vdependent upon relative `movement between said Lmembers andincluding cooperating 'fluid controlling elements engageable respectivelyivith said members for substantially balaiicingsaid feeding means with tlie drillsteel in operative position adjacent the Work. 1

20. In a drilling n'iechanisin, the combination ivith a` drilling motor, .pressure fluid actuated feeding means thereforincluding relatively movableV feeding elements, and means for vcontrolling, the pressure in said feeding vmeans including vent means for 'f ieducingtlie feeding pressure, of means dependent upon relative movement between said fee-ding elements caused by tliejreduction in feeding "pressure for substantially balancing automatically said feeding means ivlien'sai d vent means is opened.

251'. In a rock drill, the vcombination with a. drilling motor fluid actuated feeding mechanism therefor comprising relatively movable feeding elements, a main supply of pressure fluid therefor, and means for normally controlling said main fluid supply, of a supplemental supplyof pressure fluid for said feeding mechanism, and mechanically actuated means dependent upon relative movement between said feeding elements for opening automatically said supplemental supply when said main supply is closed by said controlling means, said automatic means being operative when tl'iepressure in said feeding means drops below a predetermined minimum.

22. In a drilling mechanism, the combination with a drilling motor, fluid actuated feeding means therefor comprising relatively movable feeding elements, and manu- Aally operable means for controlling the supplyof fluid thereto, of means positively actuated upon relative movement between said feeding elements to reciprocate automatically said feeding means between preidetermined limits when said manually controlled supply 'is closed by said manually operablemeans.

23. `In `a drilling mechanism, `the com bination with a drilling motor, piessiiiefliiid actuatedfeeding means therefor comprising relatively movable feeding elements, and controlling means 'for supplying :fluid to said feeding 'means to effect relative movement betiveen said feeding elements in one direction, of means autoniatically operative to admit a separate supply `of pressure fluid to said feeding means when movement between said "feeding elements occurs in an opposite direction, said automatic means including controlling elements respectively engageablev'vith said feeding elements.

In a drilling mechanism, the combination with a drilling motor, pressure actuated feedinglmeans therefor including relatively reciprocable cylinder and piston elements, fluid supply means for said feeding means, and manually operable means for controlling saidsupply to admit pressure fluid to said feeding means to effect feeding movement in one direction, of a supplemental fluid supply for said feeding means, landmeans including controlling `elen'ients respectively connected to said feeding elements and automatically operative upon relative movement between said feeding elements in the opposite direction for automatically opening said supplemental fluid supply.

i 25. Ina rock drill, in combination, a drilling motor for actuating a drill steel, pres sure Afluid actuated feeding means for said motor including relatively reciprocable fccding elements, and means for effecting con trolled supply of 'feeding pressure `fluid to said "feeding means including means for com trolling the flow of `pressure 'fluid to said feeding means'to effect feed in one direction, and automatic feed vcontrolling means dependent upon relative movement between Isaid feeding elements in the reverse direction for controlling flow `of pressure 'fluid lo said feeding means.

26. In ai rock drill, the combination with a drilling motor for actuating a drill steel, pressuieffliiid actuated feeding means .for said motor including yrelatively `reciprocablc feeding elements, and means`forcontrolling the How of pressure Vfluid Vto said feeding means to -ellect feed in `one direction, of :i supplemental fluid supply for said feeding means, and "automatic fluid controlling means dependent Yupon Ui'elativc `movement between said feeding elements inthe reverse direction lforcontrollinglthe flow of pressure fluid from said supplemental supply to said feeding means.

27. Iii a 'f roc'l drill, in. combination, a drilling motor for 'actuating a drill steel, pressure fluid actuated feedingr means `for said motor `including relatively reciprocable ill() `to said feeding means, said automatic controlling means including relatively movable fluid coiitrolling elements one of which is movable with one of said feeding elements and the other of which is operatively 'connected to the other feeding elements.

28. In a rock drill, in combination, a drilling motor for actuating a drill steel, pressure fluid actuated feeding means for said-motor including relatively reciprocable feeding elements, means for effecting controlled supply of feeding pressure fluid toV saidfeeding means ."inoluding means for controlling the flow of pressure fluid to said feeding means to effect feed in one direction, and automatic feed controlling means dependent upon relative movement between said feeding elements in the reverse direction for controlling flow Vof pressure fluid to ,said feeding means, said automatic controlling means including relatively movable Huid controlling` elements one of which is movable with one of said feeding elements and the other of which is operatively connected to the other feeding elements, :and a lost motion connection between said latter' controlling element androne of said feeding elements. Y l f 29. In a rock drill, the combination with a drilling motor for actuating a drill steel, pressure fluid actuated feeding means for said motor including relatively movable feeding elements, a passage for normally supplying pressure fluidk to said feeding means, and controlling means rfor said passage, of automatic controlling means for said feeding means operative when the pressure in said feeding means drops below a predetermined minimum and including a separate passage for conducting a supplemental supply of pressure fluid to said feeding means when said normal supply is closed, and means operative to control said last mentioned passage to control relative movement between said feeding elements including' ak control member having opposed surfaces of equal area'subjected to the .presy sure in said feeding means.

.said feeding means operative when the pressure in said feeding means drops below a predetermined minimumand including a separate passage for conducting a supplemental supply of pressure fiuid to said feeding means when said normal supply is closed, means operative to control said last mentioned passage to control relative movement between said feeding elements including a control member having opposed surfaces of equal area subjected to the pressure in said feeding means, and means operative when the `pressure insaid feeding means drops below a predeteri'nined minimum for subjecting said control member to an actuating force previously non-existent to move said member in one direction to open said supplemental fluid supply.

` 31.*In a rock drill, the combination with a drilling motor for actuating a drill steel, and pressure fluid lactuated ,feeding means for said motor including relatively reciprocable cylinder and piston elements, of means for effecting controlled supply of feeding pressure fiuid to said feeding means including automatic controlling means for controlling the feeding pressure in said feeding means including aA controlling element having equal opposed pressure areas constantly subjected to the. pressure in said feeding means, whereby said controlling element is maintained in a substantially balanced condition, and means responsive to pressure conditions said feeding means for subjecting said controlling element to a superior pressureV to unbalance said controlling element to move thel same in one direction. s i In testimony whereof I aiX my signature.

THORE RUNDQVIST. 

